Method of reducing shrinkage of wool



Patented Aug. 19, 1941 NIETHOD 0F REDFVCING SHRINKAGE 0F No Drawing. Application October 19, 1939, Serial No. 300,281

11 Claims.

This invention relates to the improvement of wool and other keratinous textile fibers, and more particularly to reduction of the shrinking tendency of such fibers.

A number of keratinous (see Lloyd and Shore, Chemistry of the Proteins, 1938, page 88) textile fibers, of which wool is the most important, are characterized by their tendency to felt when subjected to mechanical working. This felti tendency is essential in the finishing of some woolen goods to give a dense surface and in the manufacture of felts for hats, paper machine blankets, and the like. However, since it causes shrinking during laundering, it is a serious disadvantage in many wool applications. Considerable attention has therefore been given to reducing or eliminating shrinkage due to felting. For some applications, including knit goods, baby clothing, underwear, and socks, it is desirable to have the material as completely shrinkproof as is possible. For overcoats, suits, dresses, blankets, jackets, and other articles which are laundered less frequently, the shrinking tendency of the wooi need be only partially and not completely eliminated to be satisfactory in practice.

Methods previously proposed for reducing the shrinking tendency of wool include treatment with halogens, hypohalites, sulfuryl chloride and the like. However, chlorination procedures result in damage to the wool which is manifested in decreased strength, increased harshness, a slimy feel when wet, discoloration, and loss of the natural water repellency of the wool. Another disadvantage of halogenation is that tailing" effects occur, due to the rapid reaction of the halogen with the wool first entering the bath, which exhausts the reagents before all of the fabric is treated.

The use of sulfuryl chloride does not discolor and weaken the wool to the same extent as does halogenation, but the wool so treated is somewhat harsh and has lost its natural water repcllency.

This invention has as an object the improvement of the physical characteristics of keratinous textile fibers. A further object is the treatment of wool and similar keratin-containing fibers to reduce their tendency to felt on mechanical working. A still further object is reduction of the tendency of wool to shrink on laundering. Another object is the preparation of keratin-containing fibers of reduced tendency to shrink on laundering, which retain their natural water zepellency, resiliency when wet, and softness. Other objects will appear hereinafter.

These objects are accomplished by the following invention wherein a keratin-containing animal fiber, e. g., wool, is subjected to the action of an alpha-halogenated ether wherein the radicals attached to the ether oxygen contain each not more than six carbon atoms.

The shrinking tendency of wool can be reduced or completely eliminated by treating the wool with alpha-halogenated ethers in which the halogen or halogens are attached to an aliphatic carbon atom or carbon atoms and in which each organicradical separated from the remainder of the molecule by ether oxygen contains not more than six carbon atoms. More than one halogen atom may be attached to either or both of the carbon atoms linked by the ether oxygen atom and the compound may contain more than one alpha-halogen ether grouping.

Halomethyl ethers, e. g., chloromethyl ethers, that is, compounds of the structure ROCHzCl, may be readily prepared by reacting the corresponding alcohols of the formula ROH with formaldehyde and hydrogen halide, e. g., hydrogen chloride. Dlchloromethyl ether,

ClCHzOCHzCl which has proven particularly valuable in the practice of this invention and is therefore particularly preferred, may be prepared by the reaction of formaldehyde with hydrochloric acid in the presence of concentrated sulfuric acid. 2,3-dichlorodioxan, which is also particularly suited to the practice of the invention and therefore particularly preferred, exemplifies the many halogenated ethers which may readily be prepared by the reaction of free halogen with the corresponding ether. All of these methods are well known to the art.

The treatment with halogenated ethers may conveniently be carried out as follows: The wool, after preconditioning at a suitable humidity, is immersed in a vessel containing a solution of the halogenated ether. The solvent used should, of course, be an inert solvent, i. e., one which does not itself readily react with the halogenated ether under the conditions of the treatment. Hydrocarbons such as xylene, toluene, naphtha, and chlorinated hydrocarbons such as trichloroethylene and carbon tetrachloride, are suitable. Ethers, including dioxan and 1,2-dimethoxyethane, are also useful as solvents. Particularly ood results are obtained when ketones such as methyl ethyl ketone and methyl amyl ketone are employed as the solvents. The concentration of the halogenated ether in the solution, the dura It has been found that impregnation of the.

textile material with an amide such as urea be fore treatment yields particularly soft and whitewool. A weight of urea equivalent to 26% of the weight of the fibers maybe used.

In determining the shrinkprqqfness tri -e1] treated ,wool, it has been found, convenientto use a uniform testing procedure, referred to ere inafter as the laundering test. 'In thlsies nditioned overnight in a chamber maintained small sample of wool fabric treated with an alphahalogenated ether and a similar sample of.

100 (Area loss of untreated fabricarea loss of treated fabric) (Area loss of untreated fabric) Per cent shrinkproofness, i. e.,, per centreduction of tendency to shrink.

The percent shrinkproofness given-1n the following examples was determined bythis method. The laundering test is also a convenientmethod of following the shrinkproofingtreatment. since a small sample may be taken from. the textile material which is immersedin the alpha-halogenated ether solution at the end of a period judged to be suitable for obtaining the desired effect and tested in the above manner to .determine the per cent shrinkproofness. 1.1 the material has not yet been treated to;the desired=degree, the process may bexcontinued until another test indicatesthat the-desired degree-of-shrinlciproofness has been achieved.

The more detailed practice of the invention is illustrated by the following examples, wherein I parts are given by weight... -There are of course many forms of the invention other than these specific embodiments. Examplci I W001 flannel which has-been'conditioned overnight in a chamber maintained'at 100 -F."and 86% relative humidity is immersed at 140 F."for one hour in a 2% so1ution',=by volume of -dichloro-- methyl ether in' the hydrocarbon solvent having Example I! Wool flannel which has been conditioned in a chamber maintained at F. and 86% relative humidity is treated at 140 F. for an hour with a 4% solution by volume of dichloromethyl ether finfitoddard' solvent. i 'eemjfrom the 'excess soliitibrfas in --Example-= 'i lie treated wool is completely shrinkproof, as determined by the laundering test, and retains the natural res iliency soft feel. and water resistance of the untreated wool.

Etample III 1 5 7C01 i' scalred in a 4% solution of urea in. .water .,a nd.then wrung until it'contains only ,i own weight of the solution. The fabric is then 'at"'90 F. and 86% relative humidity, and then immersed for one hour at 140 F. in 5 parts by weig t of a 3.8% solution of dichloro in Stoddard solvent. The product "i h i qq i i s ms'ih water resistance of the'unt'rat'ed wot Parti ular ft e nd .es s en hi i eiE-ZQT'I .e.-.Iv .iwd 'fi i l. i In ac chamber"maintained"at ='110 FI a 80% rate humidity is' treated at 210* F, for 2 minutes 'with 7.5 parts by weight of a 2% solution byvolurn'e of' dichloroniethy l etherin Sfiid'dtuui solvent cAs s; T. v 1; as; part "1,, ;193B) The excess treating solution is removed froni-thesamplefand the wool is-rinsed in water. i T'he' shrinking-tend en'cy" of the treated'wo'ol is reduced" as per-tent, as determined bythe laundering test.

., Emmml i Wool-fiamielwhich has ee-1i nditi'e'iie'dat F. in" anatinosphere of 80%"relative'humid ity is treated at Woo-l flannel which has be ni h "l laq anifi 'm nt e a e-h id y s ar e 0.. m hours with 10 parts by "weight or -'a"'-'5.i4% solution by volume of trimethylne' l 'cqbiis chloijo "ethyl e wss aa j sa e i i fir ificfi en'c'yi ofthetrated wqor'is e ge-ed '33- percent Example VII- tains" "the'lofty handle and natural watr repel m 9 crevi w b 'gna n r fi h' a 'beeicd i qn e a fmai ms are: s humidity 'i's' treatedfor v 7.5'parts by' weightfl of' ngbutyl .chloroniethyl etlre'r in sto'ddard :61- vent. The Shrinking "tendency 0fthe treated humidity is wool is reduced 52 per cent. The flannel has an extremely soft feel.

Example IX Wool flannel which has been conditioned in a chamber maintained at 80 F. and 80% relative treated for one hour at 140 F. with parts by weight of a 2% solution by volume of 2,3-dichlorodioxan in Stoddard solvent. The shrinking tendency of the treated wool is reduced 60 per cent. The flannel retains the natural water repellency and soft feel of the untreated wool.

Example X Wool flannel which has been conditioned overnight in a chamber maintained at 92 F. and 86% relative humidity is treated for one hour at 140 F. with 6 parts by weight of a 3% solution by volume of the bis-bromomethyl ether of ethylene glycol in Stoddard solvent. The excess solution is removed from the sample which is then rinsed first in dilute ammonia solution and then in water. The treated wool retains the water repellency and softness of the untreated wool and is about 89 per cent shrinkprooi.

While normal, air-dried wool, which contains about 6% moisture, for example, wool which has been stored at 77 F. at a relative humidity of about 15%, may be used, and some effect is obtained even with bone-dry wool, it is preferred, in order to obtain more pronounced effects, to treat wool which contains about 12 to 28% moisture, for example, wool which has been conditioned at 50-100% relative humidity at 77-100" F., because more complete removal of the shrinking tendency is thereby obtained. The effect can thus be varied by controlling the moisture content of the wool to be treated. The conditioning treatment may be varied somewhat with the different types of wool to get the best results. It is, of course, possible to otbain the same percentage of moisture in the wool under different sets of relative humidity-temperature conditions. Although the wool to be treated may contain 6 to 28% moisture or'more, it is particularly preferred to employ wool which contains about 17-24% moisture.

As indicated in the above examples, the wool is treated with the alpha-halogenated ether per se. i. e., the ether as such and not in combination. Treatment of wool with the alpha-halogenated ethers in combination with other materials reactive therewith, e. g., tertiary bases, does not at:- tain the results of this invention as is further disclosed in Examples A, B, and C below. For this reason, applicant describes his treating agent as an alpha-halogenated ether wherein the radicals bounded by ether oxygen atoms are each of not more than six carbon atoms and this ether is used per se, i. e., as such and not in combination with any material reactive therewith to any substan tial extent.

Example A Wool (5.5 parts) conditioned at 78% relative humidity was treated with a solution of 1.5 parts of the bis-pyridinium salt of dichloromethyl ether in 35 parts of water at 60 C. for one hour. The reduction in shrinkage was only 8%.

Example B Wool (5.5 parts) conditioned at 78% relative humidity was treated with a solution of 1.3 parts of the pyridinium salt of n-butyl chloromethyl ether in 53 parts of water at 60 C. for one hour. The reduction in shrinkage was 8%.

Example 0 W001 (5 parts) conditioned at about 8% relative humidity was treated with a solution of 1 part of dichloromethyl ether and 0.6 part of hexameth ylenimine in 27 parts of Stoddard solvent at 60 C. for one hour. The shrinkage reduction was only 5.5%.

Any keratin-containing animal fiber, e. g., wool, alpaca, vicuna, angora rabbit hair, goat hair, and camel hair may be reduced in shrinking tendency according to this invention. The material which is to be processed may be a fabric, or may be in another form, for example, in the form of fibers, yarn, or threads.

The treatment may take place either before or after dyeing, or, if a suitable solvent is used, it may take place in the dyeing bath. Other finishing treatments can be applied before or after the shrinkproofing treatment. The duration and the temperature of the treatment are mutually interdependent. Thus, it is possible to vary the temperature within wide limits and obtain a satisfactory product. At the same time, the duration of the treatment may be correspondingly regulated. In general, it is preferred to treat the wool at -150 F. for one to two hours. However, if the temperature is raised to 210 F. a period of two minutes is suflicient to obtain a good efiect. Treatment at room temperature or below requires such extended treatment to obtain satisfactory effects that it is not ordinarily practiced. Treatment at temperatures above 210 F. is ordinarily of no particular further advantage.

The reagent may be applied either in the liquid phase, when the compound is a liquid under the conditions of the treatment, or the wool may be treated with the vapor of the compound at normal or reduced pressures, either pure or admixed with non-reactive gas. In general, it has been found preferable to apply the halogenated others from an inert solvent, i. e., diluent. From a commercial standpoint, it is often preferable to use a low concentration of the reagent in the solvent, e. g., below 10%. It is particularly preferred to use a concentration of 25%. Among the solvents which are suited for the application of the reagent are hydrocarbons or hydrocarbon mixtures such as hexane, octane, xylene, benzene, benzine, and naphtha; chlorinated hydrocarbons such as carbon tetrachloride, trichloroethylene, and perchloroethylene; ethers, including dioxan; ketones, and other inert solvents. The solvent may be recovered after each treatment, or series of treatments, for example by distillation, or it may be reused after replenishing the active agent.

From a commercial standpoint, dichlorodimethyl ether and dichlorodioxan are preferred, but any other alphahalogenated ether, including thioethers, wherein any organic radical separated from the rest of the molecule by other oxygen or thioether sulfur, i. e., each carbon chain attached to the ether oxygen or thioether sulfur contains not more than six carbon atoms may be employed to accomplish the object of this invention. There is no limitation on other groups present in the compound except that none should be present which would react with the halogenated ether, such as an amino group. For example, the compounds may contain one or more aromatic nuclei which may also contain halogen substitutes.

Aryl halogens are not necessary in increasing the resistance of the wool to shrinkage. Ethers in which the halogen atom is substituted on a saturated carbon atom are much preferred over ethers in which the halogen atom is substituted Thus when flannel is treated for 5.5 hours at on an unsaturated carbon atom. Oxygen others 77 F. and at a pH of greater than 9 with 16 are preferred to thioothcrs because of lower cost parts by weight of a 10% solution of formaldeand freedom from residual odor. hyde in water, then rinsed in water, the shrink- Thus, there may be used in the processes of tho ing tendency of the wool is not reduced.

present invention any alpha-halogenated ether, When fifty parts by weight of a solution conincluding thioether, wherein any organic radical taining 5 grams per liter of a suspension of 4 separated from the rest of the molecule by other grams of a 40% aqueous formaldehyde solution oxygen or thioethersulfur. i. e., each carbon chain with grams of 50% lactic acid and 7.5 grams attached to the ether oxygen or thioether sulfur of Monopol oil was applied to wool at 120 F. contains not more than six carbon atoms, includfor minutes and the wool then rinsed in ing the following reagents which are illustrative water, there was actually a slight increas i of compounds useful in practicing this invention: the shrinking tendency of the treated wool.

Chlorodimethyl ether ClCI-IzOCI-Ia Sym.-dichlorodimethyl ether --C1CH2OCH2C1 Unsym.-dichlorodimethyl ether CIZCHOCIIJ Chloromethyl butyl ether C1CH2OC4H9 Bromodimcthyl ether BICH2OCH3 Iododimethyl ether -JCHzOCH:

Ethylene glycol bis-chloromethyl ether- C1CH2OCHzCHzOCHgCl Trilnethylene glycol bis-chloromethyl ether C1CH2OCH2CH2CHzOCHaC1 Dibromodiethoxymethane C2H5OCBI'2OC2H5 Alpha, alpha-dichlorodiethyl ether CHa-CHCl-O-CHCl-CH: Alpha, alpha'-dichlorodiethyl sulfide--- CH3-CHCl-S-CHCl-CH3 Ethylene glycol bis alpha-chloroamyl ether C4H9CHC1O-CHzCH2-O-CHClC4H Beta-phenoxyethyl alpha-chloroethyl ether C6H6O-CH2CH2-O-CHC1CH Beta-phenoxyethyl chloromethylether Halogenated cycloaliphatic ethers, including 2,3- dichlorodioxan, may be used.

The ethers may also be defined as of the formula: R--X-R' wherein X is a member of the 6th group of the periodic table having an atomic weight not greater than approximately 32.06 (1935 Table), R and R are the non-hydroxy residues or portions of alcohols and have a chain of carbon atoms not longer than six atoms and at least one of the radicals contains a halogen on the carbon attached to the ether oxygen or thioether sulfur, i. e., on the alpha carbon. For convenience the term ether" in the claims includes both oxyethers and thioin applications of the treated wool to the manufacture of clothing, in particular baby clothing, where the comfort of the wearer is of prime importance. The fact that the wetting characterethers istics of the wool are unchanged by the treat- Although fluoro-, bromo-, and iodo-ethers ment is also of extreme mportance. Natural may be used, the chloroethers are preferred be- W001. after Cleaning, degreasing, and scouring cause they are less expensive, are more stable i markedly resistant to wetting. When wetted in storage, and are outstanding in the quality of by Prolonged Contact w moisture. it has the the products which they produce. property of taking up considerable vwater with- Combinations of halogenated ethers may be out q ngasoaked, scroopy, feel. used to reduce the shrinking tendency of the The t ges of this characteristi are Wool. obvious in the case of outer garments such as It has not been possible to advance a theory of sweaters. suits and overcoats. w v the reaction adequate to explain the shrinkprooflng advanta e s also marked in the case of clothes effect of the halogenated ethers. The shrinkt0 be Worn next to y a n the case of proofing is accomplished without destroying the u de a S. d by cl thing. The chief natural soft feel and water repellency of the advantage of w o o these uses is that due to wool. This shows that the treatment must have its free air spaces, it has a high insulating value a radically different effect on the wool from that and also retains the moisture given 03 y t e of inorganic halogen compounds such as sulfuryl y next to the skin thus retarding evap tion chloride, chlorine, or hypochlorites, organic or and Cooling o t e body surfaces. When wool is inorganic, as these reagents cause wool to bedamaged, as n p e us S kproofing treatcome harsh and to t; il ments, it takes up body moisture readily, filling Although some of the agents of this invenup th free air spaces, and also transfers moistion can be prepared from formaldehyde and turf? away from the Skin thus P i t ng more hydrochloric acid, the effect is not due to pospid e p n by air currentsn this w y sible hydrolysis to formaldehyde, as is shown by the Warmth-retaining characteristics of wool are the fact that wool treated with formaldehyde partly 105R These vantages are overcome itself is not reduced in its tendency to shrink on by the processes of the present invention wherelaundering. and by the fact that many of the y the Shrinking t y of the wool is reduced agents, including 2,3-dichlorodioxan, an espewithout destroying the natural resistance to cially effective agent, do not yield formaldehyde wetting, so that the natural insulating value on hydrolysis. of the wool is also retained. It should be pointed out, however, that the processes of the present invention do not render the wool water-proof or more resistant to wetting than the natural, untreated product. The uses for which wool of reduced shrinking tendency produced according to the present invention is particularly suited include knitted goods, such as socks, sweaters, and mufllers; woven goods such as baby clothing, underwear, suits, overcoats, sports apparel, and blankets; and the yarns or threads from which these are made.

The agents are, in general, readily soluble in common organic solvents so that the wool can be given a uniform treatment by easily prepared solutions. The action, in contrast to chlorination, is slow enough to permit of easy control by varying the duration and temperature of the treatment. Dichloromethyl ether, 9, preferred agent, is readily prepared from formaldehyde and hydrogen choride.

The above description and examples are intended to be illustrative only. Any modification of or variation therefrom which conforms to the spirit of the invention is intended to be ncluded within the scope of the clams.

What is claimed is:

1. Process for reducing the tendency of a keratinous textile fiber to shrink, which comprises treating said fiber with an alpha-halogenated ether wherein the organic radicals have each not more than six carbon atoms, said ether being employed as such.

2. Process for reducing the tendency of wool to shrink which comprises treating said wool with an alpha-halogenated ether wherein the organic radicals have each not more than six carbon atoms, said ether being employed as such.

3. Process for reducing the tendency of a keratinous textile fiber to shrink, which comprises treating said fiber with an alpha-halogenated oxyether wherein the organic radicals have each not more than six carbon atoms, said ether being employedassuch.

4. Process for reducing the tendency of wool to shrink which comprises treating said wool with an alpha-halogenated oxyether wherein the organic radicals have each not more than six carbon atoms, said ether beingemployed as such.

Patent No. 2,2 5,102.

5. Process for reducing the tendency of wool to shrink which comprises treating said wool with an alpha-chlorinated oxyether wherein the radicals attached to the ether oxygen contain each not more than six carbon atoms, said ether being employed as such.

6. Process for reducing the tendency of wool to shrink which comprises treating said wool with a,a'-dichlorodimethyl ether, said ether being employed as such.

7. Process for reducing the tendency of wool to shrink which comprises treating said wool with 2,3-dichlorodioxan, said ether being employed as such.

8. Process for reducing the tendency of a keratinous textile fiber to shrink which comprises treating said keratinous textile fiber containing from about 12% to about 28% of moisture with an alpha-halogenated oxyether wherein the radicals attached to the ether oxygen contain each not more than six carbon atoms, said ether being employed as such.

9. Process for reducing the tendency of wool to shrink which comprises treating said wool containing from about 12% to about 28% of moisture with an alpha-chlorinated oxyether wherein the radicals separated from the remainder of the molecule by ether oxygen contain eachnot more than six carbon atoms, said ether being employed as such.

10. Process for reducing the tendency of wool to shrink which comprises treating said wool containing from about 17% to about 24% of moisture with an alpha-chlorinated oxy ether wherein the" radicals, separated from the remainder of the molecule by ether oxygen contain each not more than six carbon atoms, in 2-5% concentration in an inert solvent at ISO-150 F. for 1-2 hours, said ether being employed as such.

11. Process for reducing the tendency of wool to shrink which comprises treating wool containing from about 17% to about 24% of moisture with a 2-5% solution of a,oz'-di0hl010- dimethyl ether in an inert solvent at 130-l50 F. for 1-2 hours, said ether being employed as such.

JOSEPH FREDERIC WALKER.

CERTIFICATE or" coRREcrIoN August 9: 9 4 9 JOSEPH FREDERIC WALKER.

It ishereby certified that error appears in-the-prin te'd' specification of the abovenumbered patent requiring correction as follows: Page 3, first column, line 'hl, for "otbain'f read --ob'tain--; and second-column, line 2, for "8%" .read page 5, first column, line 25, fQ'r 'ncIuded" read "included-q and that the said LettersPatent should be read with-this correction therein that the same may conformto the 'record'of the case in the Patent Office.

Signed and sealedthis 28th day. of October, A. D: 1911.1.

(Seal) Henry Van Arsdale, Acting Commissioner of Patents.

- CERTIFICATE F} CORRECTION. Patent No. 2,2 5,102. August" 19, 19141.

JOSEPH FREDERIC WALKER.

It is hereby certified that error afipegrs ir l-the-printed' specification of the above-numbered patent requiring correction as follows: Page 5, first column, line'hl, for "otbain'f read --o'titad.n--; 21nd secondeolumn, line 2,

for "81".rea d --80-; page 5, first column, line '25, for"'nc1uded" read "includedend that the said, Letters Patent should he read with this correctien therein that the seine may conform to the record of the case in the Patent Office.

Signed and sealed this 28th day of October, A. D. 19l|l.

Henry Van Arsdale, (Seal) Acting Commissioner of Patents. 

